AC 1955 then AC 1812 at Toronto Pearson
Quebec → Toronto → Cancún
Timetable, Toronto time
12:28AC 1955 from Quebec at the gate
16:10AC 1812 to Cancún leaves the gate
3 h 42 apart on the timetable
The last days
AC 1955 and AC 1812 weren’t both flown 15 min to 12 h apart in the last 21 days.
Statistics from past flights, not live flight information. Always check times and your connection with your airline, and don’t base travel or booking decisions on these numbers.